Unitary transmission for hair clippers



Feb. 13, 1951 J. OSTER 2,541,716

UNITARY TRANSMISSION FOR HAIR CLIPPERS Filed Feb. 2 3, 1945 2 Sheets-Sheet l Lin 1 r VIII/l IIIIIIIIIIIIJ III/A IIIIIIII IIIlI/II III I Jblm 55% 2F Feb. 13, 1951 J, OSTER 7 2,541,716

UNITARY TRANSMISSION FOR HAIR CLIPPERS Filed Feb. 23, 1945 2 Sheets-Sheet 2 Jbhn 05/551" SMMH'Q Patented Feb. 13, 1951 UNITARY' TRANSMISSION FOR HAIR CLIPPERS John Oster, Racine, Wis., assignor to John Oster Manufacturing Company, Racine, Wis., a. corporation of Wisconsin Application February 23, 1945, SerialNo. 579,421

3 Claims.

This invention relates. to hair clippers and re.- fers particularly to clippers of the electric motor type forming the subject matter of Patent No. 2,182,597, issued to John Oster, December 5, 1939.

In these clippers the comparatively small elec tric motor is housed within a body which serves as a handle for the clipper, and the cutting assembly comprising cooperating stationary and movable cuttersisdetachably carried at the forepart of the body to be driven by the armature shaft of the motor through asuitable transmission. employ a medially pivoted lever in the transmission means osci-llated about its pivot by rotation. of the drive shaft and having a tongue at its forward end projecting into a drive socket in the movable cutter to reciprocate the cutter upon oscillation of the lever.

This manner of driving the movable cutter is objectionable inasmuch as it requires the tongue at the forward end of the drive lever to have a more or less cylindrical surface for engagement with the sides of the driving socket in the movable cutter in order to accommodate for the relative movement between the tongue and cutter during oscillation of the lever.

Hence, a. wiping engagement on a. substantially line contact exists. between the driving tongue and the side walls of the driving socket in the movable cutter which makes rapid'we'ar on. the tongue of the driving lever inevitable.

Moreover, unless the. cylindrically shaped tongue fits substantially snugly between the sides of the driving socket in the movable cutter a clattering develops during operation of, the.

clipper because of the play at the point of connection between. the lever and movable cutter which obviously becomes more noticeable and objectionable as wear on the tongue increases.

With these objections to past constructions in.

mind, it is an. object. of the present invention to improve. the manner in which. the movable cutter is driven so as tominimize wear at said. driving, connection and. thereby largely prevent noisy operation. or clattering.

More specifically it is an object. of this invention. to provide a hair clipper of. the. character described with a driving arm for the movable cutter constrained to reciprocatory movement so as to enable substantially fiat parallel surfaces on the tongue. of relatively large area. to engage corresponding. fiat surfaces. on. the movable cutter and to. eliminate wiping engagement. there.- between.

A further object of this invention is to pro- In the past, it has been the practice to 2 vide unitary driving mechanism interposed between the movable cutter and the drive shaft of the. clipper for translating rotation of the drive shaft into reciprocation of the movable cutter.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described, and. more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

The accompanying drawings illustrate two complete examples of the physical embodiment of the invention constructed in accordance with the best modes so far devised for the practical application of the principles thereof and in which:

Figure l is a side elevational view of the forepart of a hair clipper having portions broken away and in section to illustrate the unitary drive transmission of thisinvention;

Figure 2 is a top view of the clipper shown in Figurev 1 with part of the cover broken away to better illustrate the drive transmission;

Figure 3 is a perspective view illustrating the drive transmission disassembled as a, unit from the forepart. of the body of the clipper;

Figure 4 isv a perspective view of portions of the. handle and. the forepart of the body shown.

separated to. illustrate the manner of their assembly;

Figure 5. is an exploded perspective view of. the drive transmission showing its parts in the order of. their assembly and Figure 6 is a side elevational view of a clipper similar to that of Figure 1 but provided with a modified type of cutting blade assembly.

Referring. now more particularly to the accompanying drawings in which like numerals indicate like parts, the numeral l9 designates the body of the clipper. The body Ill serves to house an electric motor (not shown) and acts as a handle for. the clipper.

The. body is'extended forwardly as at H and mounts a cutting assembly l2 at its forward extremity for ready detachment. as by means of a screw I3. The drive transmission Idof this invention is interposed between the armature or power shaft 15 of the clipper and the movable cutter l6 of the cutting assembly to translate rotation of the power shaft into reciprocation of the movable cutter, As clearly illustrated. in Figures 1 and 3,. the driving transmission I4 is. of

unitary nature and is received within a cavity [1 formed in the forepart l I of the body.

The drive transmission includes a substantially U-shaped frame I8 having a base l9 adapted to lie flatwise along the bottom of the cavity IT to be secured therein by screws 20 passing through holes in the forepart II and threaded into the base IS. The sides of the U-shaped frame provide transversely spaced standards 2! located at opposite sides of th axis of the power shaft l5, which it is to be noted, has its forward end projecting into the cavity I! to be received between the standards. The standards 2| cooperate to support a cutter actuating arm 22 therebetween by means of parallel, transverse guide pins 23 pressed into suitable holes 24 formed in downwardly depending flanges 25 at the side edges of the arm with the pins slidably received in bushings 26 carried by the standards.

The axes of the guide pins 23 line in a common plane parallel to the plane of the base I9 and are spaced apart substantially in the direction of the axis of the power shaft IE to thus constrain the driving arm 22 to translating motion in a path parallel to the base but crosswise of said axis of the drive shaft I and extending in the same direction as the path of movement of the movable cutter iii.

A tongue 21 on the forward extremit of the arm 22 engaged in the conventional driving socket 28 cut into the movable cutting blade I6 assures bodily reciprocation of the arm and cutter IS in unison. Attention is directed to the fact, however, that the sides 29 and 30 of the tongue and socket respectively are parallel and flat to provide substantial bearing area in the driving connection between these parts.

This desirable feature largely eliminates wear at the engaging surfaces of the tongueand socket to thereby preclude the clattering previously experienced upon development of such wear. These features are attained chiefly because of the reciprocating motion of the drive arm 22 and the consequent elimination of relative movement between it and the cutter 16 during operation such as was the case with the oscillating type .drive lever heretofore in use.

An upright spindle 3! carried by the base l9 medially between the standards 2| and substantially in line with the shaft l5 provides a bearing for a bevel gear 32 having a hub 33 telescoped over the spindle'3l. The gear 32 meshes with a bevel pinion 34 on the forward extremity of the drive shaft I 5 and rotation of the driven gear 32 by means of the bevel pinion is translated into reciprocation of the driving arm 22 on its guides by means of a block 35 journalled on a pin 36 carried eccentrically by the bevel gear 32.

The block 35 has a width to slidably but snugly engage between the flanges 25 of the driving arm and it is to be noted that wear between the block and these flanges is held to a minimum by engagement of relatively large flat areas on the block and flanges.

Hence, it will be seen that in the operation of the clipper, rotation of the drive shaft eliects rotation of the driven gear 32 which in turn causes the driving arm 22 and the movable cutter connected therewith to be laterally reciprocated as a unit.

It is also to be noted that the driving transmission l l may be readily replaced or removed for repair as a unit to greatly simplify maintenance of the clipper.

The frame [8 in the present case also carries the cover 31 for the transmission which is secured in position on the forepart H of the body covering the cavity ll by means of screws 38 passing through suitable apertures in the cover and threaded into suitable holes 39 in the standards. The forward end of the cover has portions bent downwardly as at 39 to form a guard for the cutting assembly in the conventional manner.

In previous clipper constructions it was the custom to provide for detachment of the forepart II of the body from the handle portion I B by means of screws passing through one of these sections to be threadedly received in the other. In the present instance, however, a novel and much more convenient detachable connection between these parts is provided as illustrated in Figure 4.

As herein shown the handle portion It] has a pilot 4d projecting axially from itsfront end portion snugly but rotatably receivable in a bore 4| formed in the rear of the forepart i l of the clipper. The pilot H3 is circumferentially recessed as at 42 at substantially diametrically opposite points to receive pins 53 embedded in the rear of the forepart H so as to project radially into the bore 4 i.

These pins are adapted to engage behind spring arms 44 secured to the end surface of the pilot is and overhanging the circumferentially recessed portions 52. If desired, the spring arms may be indented as at .5 so that they snap over the pins 43 upon rotation of the forepart H on the pilot 4!! to bring the pins from initial positions in the recesses under the arms M.

This manner of detachably connecting the forepart of the body to the handle portion H3 is exceedingly simple and advantageous in that it readily enables detachment of the entire driving head for substitution in the case of damage thereto or for replacement of the head by a shaving head or the like.

In Figure 6 a slightly modified form of cutting assembly i2 is provided which is identical to that illustrated in the aforementioned patent to John Oster. In this instance it will also be seen that the advantages derived from the employment of a bodily reciprocating drive arm 22 are retained despite the provision of a slightly modified form of cutting assembly.

From the foregoin description taken in connection with the accompanying drawings, it will be readily apparent that this invention provides a greatly improved driving mechanism for hair clippers and which is constructed to operate with a minimum of noise and of wear on the driving arm.

What I claim as my invention is:

1. Transmission mechanism adapted to be received within a cavity in the forepart of the body of a hair clipper to translate rotation of the drive shaft of the clipper into reciprocation of the movable cutter of the cutter assembly carried at the forepart of the clipper body, comprising: a relatively flat base adapted to be readily detachably secured in the bottom of said cavity at a level beneath the level of the drive shaft; a pair of standards extending upwardly from opposite sides of the base, said standards being spaced laterally from one another and adapted to receive the forward end of the drive shaft therebetween; a spindle having one end anchored in the base and extending perpendicularly upwardly therefrom between said standards, said spindle being adapted to be disposed substantially in line with the drive shaft crosswise of the axis thereof when the transmission mechanism is in place on the clipper; a gear journalled for rotation on said spindle and adapted to mesh with a suitable driving gear on the drive shaft so that the spindle gear may be rotated by the drive shaft; an eccentric pin carried by the spindle gear; an elongated cutter actuating arm carried by said standards with the arm positioned lengthwise between them and constrained to sidewise translating motion in a path above the spindle and substantially normal to the axis thereof; flanges on the cutter actuating arm disposed at opposite sides of said eccentric pin; a block journalled on said eccentric pin and engaging between said flanges to translate rotation of the spindle gear into sidewise reciprocatory movement of the cutter actuating arm; and a tongue on the end of the cutter actuating arm which is disposed adjacent to the movable cutter when the transmission mechanism is in place on the clipper connectible with the movable cutter.

2. Transmission means for translating rotation of the drive shaft of a. hair clipper into reciprocation of the movable cutter of the cutter assembly at the forepart of the clipper body, comprising: a substantially U-shaped frame readily detacha-bly securable to'the forepart of the body inside a cavity therein with the closed end of the frame against the bottom of the cavity and with the sides of the frame providing laterally spaced standards adapted to project up from the bottom of the cavity at opposite sides of the forward end of the drive shaft; an elongated cutter actuating arm positioned lengthwise between said standards and supported therefrom for sidewise reciprocatory motion across the space between the standards and in a path spaced a distance above the closed end of the U-shaped frame; a gear supported by the frame between said standards and beneath the cutter actuating arm for rotation on an axis fixed with respect to the frame and substantially normal to the path of reciprocatory motion of the cutter actuating arm, said gear being adapted for meshing engagement with a pinion on the drive shaft of the clipper; means driven by said gear and engaged between spaced abutments on the actuating arm for translating rotation of the gear into sidewise reciprocatory motion of the arm in said path; and a driving projection on the end of the cutter actuating arm which is disposed adjacent to the cutter assembly when the transmission means is in place on the clipper connectible with the movable cutter.

3. Transmission means adapted to be interposed between the cutter assembly and the drive shaft of a hair clipper for translating rotation of the drive shaft into reciprocation of the movable cutter, comprising: a frame readily detachably securable within a cavity in the body of the clipper and including a relatively fiat base adapted to lie at the bottom of said cavity at a level beneath the level of the drive shaft; a rotatable member carried by the frame for rotation on an axis fixed with respect thereto and normal to said base; means on said rotatable member for drivingly connecting the same with the drive shaft; an elongated cutter actuating arm; means mounting said arm on the frame in spaced superimposed relationship to the base, and for sidewise reciprocatory motion in a fixed path laterally across the base and substantially normal to the axis of said rotatable member; means connected between said arm and the rotatable member for translating rotation thereof into reciprocatory movement of the arm in said path; and means on the end of the arm which is disposed adjacent to the movable cutter when the transmission means is in place on the clipper adapted for engagement with said reciprocable cutter to impart reciprocatory motion thereto.

JOHN OSTER.

REFERENCES CITED The following references are of record in the file of this patent:

Oster Dec. 5, 1939 

